I will describe examples of the
application of Time-Dependent Density Functional Theory (TD-DFT) to
extended crystalline and disordered systems. I will focus on the
calculation of optical absorption spectra, and show how these can be
computed very efficiently (and typically with an accuracy comparable to
Green's function based methods) using proper formulations of TD-DFT for
extended systems. I will also address the application of TD-DFT to the
study of adiabatic dynamics in excited states, and to the description of
time-resolved electronic spectroscopy in molecules and condensed
phases.
